FAO: Stiofan RE: Adding London borough custom field

Hi Stiofan.

Sorry to bother again and again. I have a little problem to solve, and I hope you can help.

Basically, I would like to include London borough within the address, but do it programmatically. So, I have created a custom text field ‘borough’ and set it as Admin only edit.

There is this resource https://postcodes.io where you can get all location details from a postcode. So, if you search SW1A 2AA, you get json:

{
    "status": 200,
    "result": {
        "postcode": "SW1A 2AA",
        "quality": 1,
        "eastings": 530047,
        "northings": 179951,
        "country": "England",
        "nhs_ha": "London",
        "longitude": -0.127695,
        "latitude": 51.50354,
        "european_electoral_region": "London",
        "primary_care_trust": "Westminster",
        "region": "London",
        "lsoa": "Westminster 018C",
        "msoa": "Westminster 018",
        "incode": "2AA",
        "outcode": "SW1A",
        "parliamentary_constituency": "Cities of London and Westminster",
        "admin_district": "Westminster",
        "parish": "Westminster, unparished area",
        "admin_county": null,
        "admin_ward": "St James's",
        "ced": null,
        "ccg": "NHS Central London (Westminster)",
        "nuts": "Westminster",
        "codes": {
            "admin_district": "E09000033",
            "admin_county": "E99999999",
            "admin_ward": "E05000644",
            "parish": "E43000236",
            "parliamentary_constituency": "E14000639",
            "ccg": "E38000031",
            "ccg_id": "09A",
            "ced": "E99999999",
            "nuts": "UKI32"
        }
    }
}

I am after ‘admin_district’, so I am trying this snippet, which doesn’t work:

add_filter('wp_insert_post_data','_add_borough',10,2);
function _add_borough($data,$postarr){
	if(isset($data['post_type']) && function_exists('geodir_get_posttypes') && in_array($data['post_type'],geodir_get_posttypes()) && isset($data['post_title'])) {
		if(isset($postarr['zip']) && !empty($postarr['ID'])) {
			$postcode = $postarr['zip'];
			$jsonurl = "https://api.postcodes.io/postcodes/".$postcode;
			$json = $this->request($jsonurl);
			$decoded = json_decode($json);
			if($decoded->status == 200){
				$data['borough'] = $decoded->result->admin_district;
			}
		}
	}
	return $data;
}

What am I doing wrong?

Many thanks in advance,
Eugene